Britain was subjected to yet another suspected terrorist attack on Friday morning—the fifth in 2017—after what is being described as a crude device exploded on a crowded London Underground train as it pulled out of the Parsons Green station in Southwest London, according to The New York Times. The explosion, which took place at approximately 8:20 a.m., reportedly resulted in a fire on board the train and led to at least 22 people being injured with many suffering burns. No deaths have been reported at this time.

Armed police swarmed the Parsons Green station in the immediate aftermath of the attack, and they believe they have zeroed in on the device that was used to carry it out. During a press conference held shortly after the attack, one of Britain’s top counterterrorism officials Mark Rowley reported that "an improved explosive device" was the cause of the explosion. Metropolitan Police Deputy Assistant Commissioner Neil Basu, a senior national coordinator for counterterrorism policing, added that the attack is currently being investigated as a "terrorist incident."

Police have not revealed whether or not they have set their sights on any suspects yet. They have also not revealed many other details about the explosion or the device that was used during it. But there are several social media posts circulating on Friday morning that appear to show the aftermath of the incident. One Twitter post, originally posted by Twitter user @RRIGS, shows a white bucket with wires and flames coming out of it on board a London Underground train.

Another Twitter post, put up by Twitter user @sylvainpennec, features a video with that same bucket on fire inside of the train. It does not appear as though the train sustained any major damage during the attack.

There is an increased police presence both in and around the Parsons Green station on Friday morning as well as in and around other London Underground stations. A full investigation into the "terrorist incident" is expected.

President Trump responded to the news of the incident on Friday in a series of tweets. He wrote, "Loser terrorists must be dealt with in a much tougher manner," and he also alluded to his controversial travel ban in his response to what happened.

Stay tuned for further details.